The present invention relates to a monitoring system for monitoring operation of an articulated boom. More particularly, it relates to a monitoring system for monitoring position and stability of an articulated boom system which includes a base, an articulated boom and at least one outrigger.
Articulated boom systems are typically used to lift and position loads, such as pumping implements, equipment, work platforms, workers, etc., at particular elevations. For example, in concrete pumping applications, an articulated boom system is used to position a concrete distributing hose at a distant work site, normally located well off of the ground. Similarly, where a construction project requires delivery of concrete along a lengthy, above ground horizontal path, such as tunnel lining, an articulated boom system is used. Even further, articulated boom systems can maneuver the load along a relatively continuous plane. This attribute is important for many material distribution applications where an articulated boom is moved along a ceiling wall, floor, etc. while certain material such as concrete, is distributed. Through recent development, some articulated boom systems have vertical and horizontal ranges on the order of fifty meters. Articulated boom systems normally include a base such as a truck to which an articulated boom with one or more boom sections is attached, a rotational actuator mechanism such as a rack and pinion mechanism for rotating the boom, and outriggers or support legs retractably extending (e.g., by telescoping or pivoting) from the base for stabilizing the articulated boom system. Each boom section has a corresponding actuator which supports the boom section as well as any load supported by that boom section. Typically, the actuators are hydraulic piston/cylinder assemblies. Forces generated by the actuators, lifted loads, or obstacles making contact with the articulated boom, act upon articulated boom components during operation of the articulated boom system. The maximum loads or forces that the actuators, boom sections and other articulated boom system components are structurally designed to withstand are generally known by the articulated boom system manufacturer. This information may be translated into maximum loads or forces that the overall articulated boom system can support or withstand without exceeding design constraints.
Articulated boom System are frequently subjected to work conditions where the articulated boom supports loads and experiences forces that may exceed design limitations. The base serves as a strong support for the articulated boom, allowing movement to a number of positions without tipping. In other words, the articulated boom creates a moment force which is offset by the base. In addition, the outriggers are used to further stabilize the articulated boom system. The outriggers are normally deployed to their fullest extension so as to provide maximum balancing support for the entire articulated boom system. By using outriggers, the articulated boom can be maneuvered to maximize the horizontal and vertical positions without tipping. Typically, a boom operator becomes accustomed to maneuvering the articulated boom to these maximum extension positions, with the outriggers fully deployed.
At times, however, the work site does not allow for full outrigger extension. For example, when working near a heavily used street or along side a hill, one or more of the outriggers may not be able to fully extend or even extend at all. A problem can occur if the boom operator, who is otherwise accustomed to maneuvering the articulated boom to certain vertical and horizontal positions with the outriggers fully extended, forgets that the outriggers are not fully extended and attempts to maneuver the articulated boom to a position he or she has operated at in the past. However, without the extra balancing support provided by the outriggers, the force created by the articulated boom and its attached load becomes too great, causing the entire articulated boom system to tip. In this situation, potentially catastrophic results can occur with harm to human life, nearby facilities, and the articulated boom system itself.
Additional operation safety concerns arise at crowded work sites. Construction work sites often involve a greater number of possible physical obstacles, such as trees, overhead power lines, etc. The boom operator must constantly remain aware of these obstacles whenever present to avoid directing the articulated boom into contact with an obstacle. This may be a demanding task at times due to the location of the obstacle (eg. the exact location of a high power line is difficult to judge), other activities requiring the boom operator's attention, etc. Contact with certain obstacles, such as trees or buildings, may damage the articulated boom system or cause it to tip. Even worse, some obstacles, such as power lines can cause severe injury or death to the operator if contacted. Thus, safe operation of an articulated boom system requires frequent monitoring of the position of the articulated boom along with the location of any obstacles.
Therefore, in view of the above problems associated with articulated boom system operation, a substantial need exists for a monitoring system for monitoring the position and stability of an articulated boom system, and warn or otherwise prevent the articulated boom from moving into a tipping situation, or contacting work site obstacles.